Out of the River × Master box set, this was probably the one I was looking forward to the most, having heard some of the War Master stories and really enjoying them, but in the end it turned out to be the one I liked the least!

Unfortunately if you put a picture of the War Master on the artwork, and sell this as part of a 4 part series where River meets an incarnation of the Master, but then try and make the first half of the story a "whodunnit" with River believing it is actually the Doctor (something already done a couple of times now...), then you're just going to make River seem dumb (fool me once, shame on you, fool me twice, shame on me!) and also make the first half drag on.

It doesn't help that the plot, of a rogue AI and members of a space ship being knocked off one by one, has all been done better before.

When the Master is actually revealed it is a lot of fun, and there are some great one-liners and brilliant performances as always. It's just a bit of a slog to get there, and then not enough happens at the end.

Plus the ending is very strange - the Master hypnotises River so she gives false testimony and hides the fact that the Master was ever there. Since when does he care who finds out about his evil plots? And how did River break the time-lock to get involved in the Time War at all??

It's a shame, but this is the weakest of the set.